TDA8295_09 Datasheet, PDF (38/83 Pages) NXP Semiconductors – Digital global standard low IF demodulator for analog TV and FM radio

NXP Semiconductors
TDA8295
Digital global standard low IF demodulator for analog TV and FM radio
9.3.12 SSIF and mono sound settings
Table 37. SOUNDSET_1 register (address 20h) bit description
Legend: * = default value.
Bit
Symbol
Access Value Description
7
-
R/W -
not used
6 and 5 AM_FM_SND[1:0] R/W
Output mode for inbuilt FM/AM mono sound
demodulator
01*
FM sound
10
AM sound (only L/L-accent standard)
XX
don’t care if SSIF output is chosen
(SSIF_SND[1:0] = 10)
4 to 0 DEEMPH[4:0]
R/W
mono sound de-emphasis adjustment to
compensate transmitter pre-emphasis; or
low-pass filter to remove out of audio band
interferers
0 0001*
de-emphasis of 75 μs for M/N standard or
non-European FM radio to compensate the
transmitter pre-emphasis
0 0010
de-emphasis of 50 μs for B/G/H, D/K and
I standard or European FM radio to
compensate the transmitter pre-emphasis
0 0100
low-pass filter with 30 kHz −3 dB cut-off
frequency to remove out of audio band
interferers
0 1000
low-pass filter with 140 kHz −3 dB cut-off
frequency to drive an external BTSC stereo
decoder
1 0000
The de-emphasis filter is bypassed. This
can be used for debugging or other
purposes.
Table 38. SOUNDSET_2 register (address 21h) bit description
Legend: * = default value.
Bit
Symbol
Access Value Description
7 to 5 -
R/W -
not used
4
HD_DK
R/W
When active, the internal FM mono sound
demodulator can handle excessive FM deviations up
to 400 kHz. This might happen in D/K standard China.
To activate this mode, it is mandatory to set
D/K standard first. The sound output level has to be
adapted accordingly by the microprocessor to avoid
sound DAC clipping. E.g. for 400 kHz FM deviation,
the −12 dB setting of the sound level register
(see Table 39) is recommended.
0*
high Deviation mode off
1
high Deviation mode on
X
don’t care if SSIF output is chosen
(SSIF_SND[1:0] = 10)
TDA8295_C2_2
Product data sheet
Rev. 02 — 27 November 2009
© NXP B.V. 2009. All rights reserved.
38 of 83